Sublingual immunotherapy for latex allergy: tolerability and safety profile of rush build-up phase

OBJECTIVE: Sublingual immunotherapy represents an efficient therapeutic tool for the management of latex allergic patients. Local and systemic adverse reactions are reported, and risk factors for those reactions are poorly understood. The aim of this study is to compare two different rush induction protocols (2-day and 3-day) in terms of safety and tolerability and effectiveness in reaching the maintenance dose. METHODS: Twenty-three outpatients (F/M = 18:5; 5-64 years of age), with latex allergy were randomly assigned to: Group 1 (2-day) and Group 2 (3-day). Adverse reactions were classified by their type and severity. RESULTS: Twenty-one subjects, 10 from Group 1 and 11 from Group 2, reached the maintenance dose, 70% of them without side effects. Seven adverse events were reported in Group 1: three were local (oral itching) and spontaneously remitted; four were systemic (Grade-2: two reactions; Grade-3: two reactions) and were effectively controlled with drugs. The protocol was interrupted in two cases because of recurrent reactions. No reactions were reported in Group 2. Age, gender, atopy, specific IgE, skin prick tests and sublingual challenge did not seem to influence the risk of side effects significantly. No significant modification of skin tests and specific IgE levels were reported in both groups. The cutaneous test turned negative in 16 patients, eight from Group 1 (80%) and eight from Group 2 (73%). The remaining patients (two from Group 1 and three from Group 2) showed a reduction of latex reactivity, in terms of symptom score (MIS: 2 vs. 0.5 in Group 1, 3 vs. 1 in Group 2). CONCLUSIONS: This study confirms the safety of rush induction. The 3-day protocol was better tolerated than the 2-day. Significant risk factors for the occurrence of adverse reactions were not identified. Only the type of protocol but not patient-related parameters seemed predictive of side-effects.